Conventionally, in order to display a high-reality image, an image display system for displaying a three-dimensional image of an object in space has been developed. As an example of such a system, Patent Literature 1 discloses a three-dimensional image projector that projects an image in a direction set in advance at the time of recording of a hologram. The three-dimensional image projector displays a three-dimensional image having high reproducibility according to a change in the position of the viewer.